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  <meta charset="UTF-8">
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  <title>制作一个三角形</title>
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<body>
  <h3>制作一个三角形</h3>
  <p>
    通过给边框增加宽度，并设置颜色即可做出三角形
  </p>
  <div style="width: 0px;border-width: 100px;border-style: solid;border-color: red blue green chocolate;">
  </div>
  <div style="width: 0;border-width: 100px;border-style: solid;border-color: transparent transparent transparent chocolate;">
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